A Whanganui woman is furious about the tactics used by a scammer who called her mother's landline recently.
Sandra Fraser said her 90-year-old mother, who lives in a rural area, received a call from a man who claimed to work for Spark.
"Mum has her account with Spark so she believed the call was genuine," Fraser said.
"He told her that he was a fraud investigator employed by Spark and said he needed her bank account details."
Fraser said an attempt was made to withdraw $7000 from her mother's account later that evening.
"He called her back and tried to get her to change her password.
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"I was there when he called back and when I told him I knew what he was up to, he still tried to insist that he worked for Spark."
After alerting police, Fraser contacted her mother's bank.
"They responded really well and Mum was reassured that he couldn't access her money but it was very distressing for her."
Spark corporate relations spokeswoman Sam Smith said there has been a marked increase in scammer activity recently.
"Over the past few years, there has been an increase in scammers pretending to be from well-known companies like Spark, other telcos or banks to trick or intimidate people into handing over personal information or allowing access to their personal computers.
"These fraudsters often monitor corporate activity and mimic their methods of communication, so it can be difficult for customers to tell the difference between what's genuine and fake."
Smith said the most important thing to remember is that Spark will never call customers out of the blue to ask for personal details like bank account, credit card or internet banking numbers or to request access to your personal computer or laptop.
"If the person tries to convince you they are from Spark by supplying a phone number to ring back, don't use this.
"Get in touch with us directly by calling 0800 800 123 if you want to check if the call was genuine."
Age Concern Whanganui manager Michelle Malcolm said she had not heard about the Spark fraud investigator claim.
"That's a new one on me and I'll add it to our list of scam alerts.
"I'm pleased to say I haven't been hearing about the ones claiming to be from IRD or offering holidays of a lifetime recently."
Ministry of Business, Innovation & Employment consumer protection manager Mark Hollingsworth said scams are becoming more sophisticated and advised the reporting of all suspicious calls.
"If someone contacts you unexpectedly, you should always consider the possibility that it may be a scam.
"Reports build a dashboard of information which helps to track trends in scams and this tracking is used to create effective public awareness warnings."
He advises reporting all suspicious calls to Netsafe by calling the toll free on 0508 NETSAFE (0508 638 723) or visiting the website.